/*
 * $Header$ $Revision:400312 $ $Date:2006-05-06 14:49:41 +0200 (Sat, 06 May
 * 2006) $
 *
 * ====================================================================
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with this
 * work for additional information regarding copyright ownership. The ASF
 * licenses this file to You under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many individuals on
 * behalf of the Apache Software Foundation. For more information on the Apache
 * Software Foundation, please see <http://www.apache.org/>.
 */

package com.microsoft.tfs.core.httpclient.cookie;

import java.util.Comparator;

import com.microsoft.tfs.core.httpclient.Cookie;

/**
 * This cookie comparator ensures that multiple cookies satisfying a common
 * criteria are ordered in the <tt>Cookie</tt> header such that those with more
 * specific Path attributes precede those with less specific.
 *
 * <p>
 * This comparator assumes that Path attributes of two cookies path-match a
 * commmon request-URI. Otherwise, the result of the comparison is undefined.
 * </p>
 *
 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
 *
 * @since 3.1
 */
public class CookiePathComparator implements Comparator<Cookie> {
    private static String normalizePath(final Cookie cookie) {
        String path = cookie.getPath();
        if (path == null) {
            path = "/";
        }
        if (!path.endsWith("/")) {
            path = path + "/";
        }
        return path;
    }

    @Override
    public int compare(final Cookie c1, final Cookie c2) {
        final String path1 = normalizePath(c1);
        final String path2 = normalizePath(c2);
        if (path1.equals(path2)) {
            return 0;
        } else if (path1.startsWith(path2)) {
            return -1;
        } else if (path2.startsWith(path1)) {
            return 1;
        } else {
            // Does not really matter
            return 0;
        }
    }
}
